From patchwork Mon Jun 1 10:46:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanley Chu X-Patchwork-Id: 11581861 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2ACC960D for ; Mon, 1 Jun 2020 10:47:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11DEE20772 for ; Mon, 1 Jun 2020 10:47:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="A7SGOhvh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726936AbgFAKq7 (ORCPT ); Mon, 1 Jun 2020 06:46:59 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:29099 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726078AbgFAKqv (ORCPT ); Mon, 1 Jun 2020 06:46:51 -0400 X-UUID: 931f637218ee4d9da891b52c24ce2845-20200601 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=ew+RGCuaV2Y1qHcybtLqf6q5Y9tu1r8jPZYZhoV+ToI=; b=A7SGOhvht8wg2PLc3KmLquUNvZkUAe0xivrZoBQTKyf0lXl/uu6Qba4BlrVx4AdRLS+l5FERi3m50Mly/90752MweMcSg+n5EKwPPKpjWhXDpO3P88DpzdpK2SJqmhW/kGefAtQeCwESpORnQj0m/THGDF5ywBQDzmUgINptH44=; X-UUID: 931f637218ee4d9da891b52c24ce2845-20200601 Received: from mtkcas06.mediatek.inc [(172.21.101.30)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0809 with TLS) with ESMTP id 85323176; Mon, 01 Jun 2020 18:46:49 +0800 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkmbs02n2.mediatek.inc (172.21.101.101) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 1 Jun 2020 18:46:46 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 1 Jun 2020 18:46:45 +0800 From: Stanley Chu To: , , , , CC: , , , , , , , , , , , , , , Stanley Chu Subject: [PATCH v3 2/5] scsi: ufs-mediatek: Do not gate clocks if auto-hibern8 is not entered yet Date: Mon, 1 Jun 2020 18:46:43 +0800 Message-ID: <20200601104646.15436-3-stanley.chu@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20200601104646.15436-1-stanley.chu@mediatek.com> References: <20200601104646.15436-1-stanley.chu@mediatek.com> MIME-Version: 1.0 X-TM-SNTS-SMTP: A3A38F099F244B213021D7716C53E5E2CFB044CE2A7C2B50457DA796582604B42000:8 X-MTK: N Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org There are some chances that link enters hibern8 lately by auto-hibern8 scheme during the clock-gating flow. Clocks shall not be gated if link is still active otherwise host or device may hang. Fix this by returning error code to the caller __ufshcd_setup_clocks() to skip gating clocks there if link is not confirmed in hibern8 state yet. Also allow some waiting time for the hibern8 state transition. Signed-off-by: Stanley Chu Reviewed-by: Andy Teng --- drivers/scsi/ufs/ufs-mediatek.c | 36 ++++++++++++++++++++++++--------- 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c index 523ee5573921..3c85f5e97dea 100644 --- a/drivers/scsi/ufs/ufs-mediatek.c +++ b/drivers/scsi/ufs/ufs-mediatek.c @@ -178,15 +178,30 @@ static void ufs_mtk_setup_ref_clk_wait_us(struct ufs_hba *hba, host->ref_clk_ungating_wait_us = ungating_us; } -static u32 ufs_mtk_link_get_state(struct ufs_hba *hba) +int ufs_mtk_wait_link_state(struct ufs_hba *hba, u32 state, + unsigned long max_wait_ms) { + ktime_t timeout, time_checked; u32 val; - ufshcd_writel(hba, 0x20, REG_UFS_DEBUG_SEL); - val = ufshcd_readl(hba, REG_UFS_PROBE); - val = val >> 28; + timeout = ktime_add_us(ktime_get(), ms_to_ktime(max_wait_ms)); + do { + time_checked = ktime_get(); + ufshcd_writel(hba, 0x20, REG_UFS_DEBUG_SEL); + val = ufshcd_readl(hba, REG_UFS_PROBE); + val = val >> 28; + + if (val == state) + return 0; - return val; + /* Sleep for max. 200us */ + usleep_range(100, 200); + } while (ktime_before(time_checked, timeout)); + + if (val == state) + return 0; + + return -ETIMEDOUT; } /** @@ -221,10 +236,13 @@ static int ufs_mtk_setup_clocks(struct ufs_hba *hba, bool on, * triggered by Auto-Hibern8. */ if (!ufshcd_can_hibern8_during_gating(hba) && - ufshcd_is_auto_hibern8_enabled(hba) && - ufs_mtk_link_get_state(hba) == - VS_LINK_HIBERN8) - ufs_mtk_setup_ref_clk(hba, on); + ufshcd_is_auto_hibern8_enabled(hba)) { + ret = ufs_mtk_wait_link_state(hba, + VS_LINK_HIBERN8, + 15); + if (!ret) + ufs_mtk_setup_ref_clk(hba, on); + } } } else if (on && status == POST_CHANGE) { ret = phy_power_on(host->mphy);